Austenitic nickel alloy

Abstract

The invention relates to an austenitic nickel-chromium-molybdenum alloy having high resistance to general corrosion, crevice, pitting and stress crack corrosion and also intercrystalline corrosion, consisting of (in % by weight): carbon: up to 0.01% silicon: up to 0.05% manganese: up to 0.50% phosphorus: up to 0.020% sulphur: up to 0.010% chromium: 14.0 to 18.0% molybdenum: 14.0 to 18.0% cobalt: up to 2.0% tungsten: up to 0.5% calcium 0.001 to 0.010% magnesium: 0.001 to 0.020% aluminium: 0.05 to 0.30% nitrogen: up to 0.02% iron: up to 3.0% copper: up to 0.5% titanium: up to 0.01% residue nickel and usual impurities due to melting, the sum of the contents (carbon+silicon+titanium) being limited to 0.05% at the most, and the sum of the elements (calcium+magnesium+aluminium) being adjusted within the limits 0.055 to 0.33%.

We claim: 
     
       1. An austenitic nickel-chromium-molybdenum alloy having high resistance to general corrosion, crevice, pitting and stress crack corrosion and also intercrystalline corrosion, consisting essentially of in % by weight: carbon: up to 0.01%   silicon: up to 0.05%   manganese: up to 0.50%   phosphorus: up to 0.020%   sulphur: up to 0.010%   chromium: 14.0 to 18.0%   molybdenum: 14.0 to 18.0%   cobalt: up to 2.0%   tungsten: up to 0.5%   calcium: 0.001 to 0.010%   magnesium: 0.001 to 0.020%   aluminum: 0.05 to 0.30%   nitrogen: up to 0.02%   iron: up to 3.0%   copper: up to 0.5%   titanium: up to 0.01%   balance nickel and residual impurities,   the sum of the contents of being limited to 0.05% at the most, and the sum of the elements being within the limits 0.055 to 0.33%.   
     
     
       2. A constructional member in an electrolytic treatment plant for the surface treatment of metal strips made from the austenitic nickel-chromium-molybdenum alloy of claim 1. 
     
     
       3. A roller for an electrolytic strip galvanization plant made from the austenitic nickel-chromium-molybdenum alloy of claim 1. 
     
     
       4. A material for handling chemical process media and hot contaminated mineral acids with satisfactory resistance to wet chlorine gas, hypochlorite and chloride oxide solutions made from the austenitic nickel-chromium-molybdenum alloy of claim 1. 
     
     
       5. An absorber component for the purification and desulphurization of flue gases made from the austenitic nickel-chromium-molybdenum alloy of claim 1. 
     
     
       6. A material for pickling bath tanks and associated components, and installations for the regeneration of pickling baths, made from the austenitic nickel chromium molybdenum of claim 1.